kodi is software installed on a customers computing device
my setup at home has kodi reading off an external HDD more than anything else. Individual streaming services are plugged in to kodi and pick up their content in accordance with the means by which that streaming service works. Most streaming services are "proper" streaming services and kodi is awesome at getting the streaming services running on an entertainment system. Some services use weird and wonderful (often not so wonderful) ways of doing things and if so then yes you could have p2p traffic.
Is there any way of testing how much streamed content reflects as P2P? This could potentially make or break home basic uncapped accounts if clients are under the impression its all going through normal streaming.

well done CW.